Enter your Drive Voltage, Baud Rate, Cable Length, Node Count, Termination Type, and Ambient Temperature into the CAN Bus Termination Calculator to find your ideal Termination Resistance, Min Power Rating, Max Current, Bus Capacitance, and Max Bus Length.
Termination Resistance
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Minimum Power Rating
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Maximum Current
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Bus Capacitance
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Maximum Stub Length
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Standard Resistor Value
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CAN bus termination prevents signal reflections at the ends of the bus cable. Without proper termination, reflections can cause communication errors and unreliable data transmission. Standard termination uses 120Ω resistors at each end of the bus.
For standard CAN buses, use 120Ω resistors at both ends. The total parallel resistance should be 60Ω. For high-speed applications or long cables, consider split termination with additional capacitors for better signal integrity.
Power rating depends on the drive voltage and current through the resistor. Calculate using P = V²/R and apply a safety factor of 2-3x for reliability. Typical values range from 0.25W to 1W for automotive applications.
Split termination is recommended for high-speed CAN (>500 kbps) or noisy environments. It uses two resistors in series with a capacitor to ground, providing better common-mode noise rejection and EMI performance.
Longer cables increase capacitance and propagation delay. For cables over 100m, you may need to reduce baud rate or use repeaters. Maximum stub length also decreases with higher baud rates to maintain signal integrity.
Improper termination causes signal reflections, voltage level errors, and communication failures. Over-termination (too low resistance) increases current consumption, while under-termination causes signal integrity issues and potential data corruption.
Standard CAN uses 120Ω termination regardless of baud rate. However, the cable length and stub length limits change with baud rate. Higher baud rates require shorter cables and stubs for reliable operation.